Electric flush toilets.
With Marine Electric flush systems the pumping is activated by a simple wall mounted switch or foot pedal that activates the pump and or macerator to empty the toilet. Installed below or above the waterline they are self priming to 4′. Using a 12-volt DC motor they can macerate waste and rinse the bowl with a self-priming action. Some electric toilets are available with the choice of fresh water or raw water flushing. Fresh water flushing prevents the odors generated by raw water organic materials such as seaweed getting trapped in bowl rim or the microbes in the raw water dying in the line between the hull and head.
Forget About It For Boats is compatible with and will compliment any of the electric flush marine heads by eliminating the off gassing that causes and consuming the sludge to water.